The overall research program proposed here is designed to determine the effectiveness of passive serum therapy to the control of malignant growths. In order to broaden the applicability of the results obtained, several tumor systems are being explored (leukemia, sarcoma, carcinoma) primarily utilizing inbred mice. Special attention is being devoted to two aspects of this problem. First, we are seeking to devise the most efficient and safe protocols by judiciously choosing our target antigens and the corresponding antibodies. Secondly, the underlying mechanisms responsible for successful tumor control or rejection are being actively investigated. Major emphasis is being placed on approaches for immunological management of non-antigenic tumors. We have found that such can be rendered antigenic and responsive to immunological management subsequent to superinfection in situ with viruses. Tumor models are being developed in marmosets in order to extend this approach to primates. Finally, the significance of the elevated levels of IgA in secretions from lung cancer patients is under continuing investigation, as is its value as a diagnostic tool for the disease.